Efficacy of Left Atrial Voltage‐Based Catheter Ablation of Persistent Atrial Fibrillation

Abstract

Additional LVZ-based substrate modification after PVI improved the outcome in PeAF patients with LVZs, whereas PVI alone worked in patients without LVZs, even in those with PeAF.

Effect of ablation at high‐dominant frequency sites overlapping with low‐voltage areas after pulmonary vein isolation of nonparoxysmal atrial fibrillation

“…Bipolar electrograms were filtered by a bandpass to frequencies between 30 and 500 Hz. In accordance with the previous studies, an LVA was defined as an area with a bipolar peak‐to‐peak electrogram amplitude of < 0.5 mV and electrical scar areas as < 0.1 mV and covering > 5% of the LA body surface area. The LA surface area was defined as the LA body area without the PV antrum regions inside the PVI line.…”

“…In this study, the extent of the LVZ was categorized on the basis of the LA fibrosis grade evaluated by delayed‐enhancement magnetic resonance imaging (MRI) . Various additional LVA‐based substrate modification procedures after the PVI have been reported in patients with nonparoxysmal AF having LVAs . In many patients with AF, individually located sites and/or patchy fibrotic areas targeted specifically for ablation have been found.…”

“…After the PVI, DF mapping, and ablation, a detailed bipolar LA voltage map was constructed during SR in all patients after external cardioversion. The LVA mapping method has been described previously . The mapping points were systematically acquired with a decapolar circular catheter (Inquiry Optima or Reflexion Spiral; St. Jude Medical).…”

“…Notably, a new strategy based on low‐voltage areas (LVAs) as detected by left atrial (LA) voltage mapping during sinus rhythm (SR) has recently been reported because LVAs are a predictor of AF recurrence after AF ablation . However, the approach for various additional LVA‐guided substrate modification procedures after the PVI in patients with nonparoxysmal AF is very complicated due to the size and distribution of the LVAs . Ablative substrate homogenization or linear lesions to isolate the LVAs may produce new tachyarrhythmias .…”

Strategy and Outcome of Catheter Ablation for Persistent Atrial Fibrillation ― Impact of Progress in the Mapping and Ablation Technologies ―

“…41 Catheters with smaller electrodes and closer interelectrode spacing may be suitable to determine the area of low voltage more accurately. Yamaguchi et al demonstrated the usefulness of regional ablation of low-voltage areas (Figure 3), 39 while Kottkamp et al proposed circumferential isolation of lowvoltage areas, so-called box isolation of fibrotic areas (BIFA) (Figure 4). 36 BIFA would be suitable for patients with massive fibrosis in the LA, although its effect in such cases is reported to be limited.…”